When on demand processing is performed in an environment in which processing systems for transaction processing are clustered, a method is commonly used in which requests from threads to processing systems are allocated by allocating apparatus such as a gateway. For example, in one product, a connection pool contains a plurality of connections to a function on the gateway (queue manager) for transferring messages. When messages are transferred, a transfer destination is determined by a thread acquiring a connection from the connection pool in a round-robin manner.
The technique used to select and establish a connection to a database instance via a connection pool is well known as described in International Application No. 2008-525916 (Patent Literature 1).
The technique used to establish the priority among channels using a round-robin manner is also well known as described in Laid-open Patent Publication No. 08-249269 (Patent Literature 2).